Expansion reamer



March 4, 1924.;

M. A. HERRO EXPANSION REAMER Filed Jan. 16, 1923 the holder.

Patented Mar. 4, i924.

on sas ea c.

' Moses A. HER-R0, or OCONOMOWOC, WISCONSIN.

EXPANSION REAMER.

Application filed January 16, 1923. Serial No. 612,896.

To all whom it may concern: available, so that the blade may be advanced Be it known that 1, Moses A-..Hnnno,a a considerable distance. citizen of the United States, and resident of With the above and other objects in view, Oconomowoc, in the county of 'Waukesha which will appear as the description pro- 5 and-:Stateof \Visconsin, have invented cerceeds, the invention resides inthe novel contain newH-andvuseful Improvements in Exstruction, combination and arrangement 0 ansionReamers; .and I 'do hereby declare parts substantially as hereinafter described that the following is a full, clear, and exact and more particularly defined by the apdescription thereof. pended claim, it being understood that such 10 Thisinvention comprises a plurality of changes in the precise embodiment of the ream'er blades, provided with rack ortions, herein disclosed invention may be made as aholder for the blades, a spindle having a come within the scope of the claim. gearportion for advancing the blades from In the accompanying drawing is illusthe holder andmeans for-locking the blades ed one complete example of the physical 15 in adjusted position. embodiment. of the present invention con- The primary object of the invention structed according to the best mode so far is convenience and rapidity of adjustment. devised for the practical application of the The movement of the blades outwardly is principles thereof. effected by the mere rotation of the spindle Figure 1 is a longitudinal section on the 20 with respect to the blade holder. The teeth line 1-1 of Figure 2.

on the spindle meshing with those on the Figure 2 is a section on the lime-2 of blades, operateson rotation .of'the spindle Figure 1. v 4

to advance all of the blades an equal extent, Figure 3 is a section showing a modified so that the edges of the blades lie on the rm ofreaming blade.

25 rf f an i agi ry yli der d are The spindle comprises a rectangular pordisposed for-effective reaming action, i101! 10 adaptedto be inserted into 3. chuck An object oft-he invention is the effective for gripping a portion of a tool suitable'for ri i iti f th blad Th rotating the. reamer, an adjacent threaded cylindrical holder is provided with a recess p r ion 11; spaced cylindrical portions 30 for each of the bladesand nuts are threaded 12-42, and a threaded portion 13 at the on the spindle and are eiiective to rigid with the holder, so that the blades are t een cylindrical portions 12-12. Aholdsecurely positioned and maintained against ng ylind r 15 PS the g a Portion movement in .any direction with respect to 14 and fits about cylindrical portions 12-12.

' The cooperative relationship of the cylin- An object of the invention is the provision drical portions and the holder is suchfthlat t e of means by which the extentof extension of here is no. possibility of wobblin'g o the blades can be immediately determined. holder a-ndcylin der. Nolateral movement One .or more of thebladesis provided with of any part thereof, with respect to the 40 graduations which maybe inspected'to despindle, is possible. In otherwords, due to termine the distance of projection of the the four point cutting action of the reamer, blade from the holder. In this manner, the irregular boring or angular distortion of diameter of thebore in which th blades the bored hole willnot result as frequently are operative 'inadjusted position is dehappens in a two blade reamer.

ea termined at once. Blades 16-16, which are substantially A still further objectof the invention is identical and blades 17-17 which are subthe provision of a construction whichmakes stantially identical, are provided, the holdpossible a. maximum extensibility ofthe ing cylinder having arecess for each of the a slidlng fit in blades, so that. the reameris operative in a blades, the blades having des is beveled at;

50 bore of large diameter. When the blades the recess. Each of the bla are in their most retracted position, considerits cutting edge. Blades 16 is provide able lengths of rack portions are disposed on a 'pair of smaller rack portions 18-18, both sides of' the spindle. Consequently, rectangular in shape and spaced apart. 'Beupon the rotation of the spindle a considertween the rack portions 18-18 the blade 55. able length of rack portion for each blade is extends in a relatively narrow strip. It exl k it end and a gear portion. 14, extending betends also in relatively narrow strip beyond rack portion 18. The blade 16 is provided with rack portions similar to those of blade 16. Knife 17 is provided With rack portions ill-19 and blade 17 is provided with rack portions 20-20. Rack portions 19 and 20 are spaced fromrack portions 19 and 20, respectively, so as to receive therebet'vveen rack portions of blades ill--16. Rack portions 1616 are spaced apart to receive therebetvveen portions l920. lln adjusting the blades, the spindle is rotated With respect to the holder 15 and the meshing teeth of the rack portions and gear portion 14 are operated to move outwardly the blades. ()bviously, the advancement of all of the blades is equal, so that the edges are at all times disposed on the surface of an imaginary cylinder, and

an efiective reaming action. is insured. The

surfaces of the rack portions farthest from the spindle are smooth, so that they slide freely over the contiguous portions of the holding cylinder. The rack portion 19 is provided in its outer surface with a groove for the reception of the end of a screw 21, which operates to limit the outward movement of blade 17. W hen the outward move ment out the knife 1? is stopped, blades l6-l6 and 17 are also stopped as the spindle is prevented from further rotation.

Blade 16 is provided at one end with graduations 22, extending from the edge of the blade to the surface of the cylinder. These graduations may be inspect-ed to termine the degree of extension of the blade, or in other Words, the diameter of the bore in which the instrument is designed to fectnate reaming action, By the mere rotation. of thespindle the operator i enabled extend the blades to a desired degree. the raclr portions of the blade are spaced apart, the of the blade is held outward rig dly, so that there is no possibility of deflection inwardly of any portion of the blade. l1 desired, gradnations may be made on each of the blades.

A ter the blades are 2tCl]I1St{l to a proper position, nut 23 on threaded portion lland nut 24 on threaded portion 13 are caused to approach so as to effectively grip the ends of the cylinder and lock the blades rigidly in position, To again adjust the instrument,

mits the rack portions 'tively, each of the rack bla'le Wisconsinh fore in a minimum extensibility, as it per- 5 of one blade to cross the rack portions of two other knives.

In the modification. shown in Figure 3, blades 25, 26, 27 and 28' are provided with rack portions 25, 26, 2'? and 28' respecportions being co extensive with itsblade and uninterrupted. @bviously, the blades of Figure 3 cannot be extended so far as those in the modification oi Figures 1 and 2, as the rack portions have not sui ricient' idth.

In both of the modifications, the blades are secured rigidly 'in position and disposed at all times with their edges in etiective reaming position.

l claim:

An expansion reanier comprising a holder having a cylindrical opening thcrethrough and having four pair of slots extending from said opening outwardly, said pairs or slots being arranged successively at right angles to each other, spindle in said opening having elongated gear teeth upon the portion enclosed by said holder, said spindle having threaded ends projecting beyond said holder, nuts upon said threaded ends adapted to loclr said spindle relative to; said holder, and four elongated cutting projecting 'froin said holder and each having a ct inwardly extending spaced arms positioned in said slots provided with ree teeth meshing with said gear teeth, the arms of one blade intern esh-ing With the arms of the succeeding blade, whereby said blades may be greatly extended and Whereby said blades supported at spacedpoints.

In testimony tl" l have hereunto se in the county c m all a the "foregoing hand at ivlilwaukee, livaulree and State of 

